Nan Madol

The ancient city of Nan Madol is situated just off the coast of Micronesia, and to say it has scientists baffled would be an understatement. Constructed on top of a coral reef, the city is built out of giant basalt blocks, which collectively weigh an estimated 250 million tonnes. Moving that amount of stone across the ocean would be an impressive feat by today’s standards, but Nan Madol dates back to around 2,000 years ago. Researchers are equally in the dark about what happened to the civilisation that built it, as they seem to have disappeared without a trace.

Nazca Lines

Diego Delso/Wikimedia

Sometime between 100 and 700 AD, an ancient Peruvian civilisation carved giant pictographs into the soil of the Nazca desert. These images – which include depictions of monkeys, birds and spiders – measure between 400 and 1,000 metres. Scientists are absolutely baffled as to how the pictograph’s primitive creators were able to keep them perfectly proportioned, as they can only be viewed in their entirety from hundreds of feet in the air.

Sacsayhuaman

Sacsayhuaman/Wikimedia

Sacsayhuaman is a towering stone structure constructed sometime in the 15th century by the Incas in Peru. The site is teeming with mysteries, with scientists unsure whether the structure was used as a fortress or for ceremonial purposes. Other unanswered questions include how the stones – some of which weigh over 100 tonnes – were moved by the Incas, and how they managed to make them fit together so well that the structure has remained standing for hundreds of years.

Coso artefact

Pierre Stromberg/Wikimedia

On February 13th, 1961, a group of prospectors dug up what appeared to be a 1920s spark plug. This wouldn’t have been particularly noteworthy, were it not for the fact that the spark plug was incased in a geode that was estimated to be around 500,000 years old. Considering that modern humans didn’t evolve until 200,000 years ago, this discovery could point to the existence of an ancient civilisation that consisted of a different species altogether.

The Dropa Stones

Discovered in a Chinese cave in 1938, the Dropa Stones are ancient stone discs that strongly resemble gramophone records, with a hole in the middle and a spiral groove carved into them. Upon closer inspection, that groove was discovered to contain hieroglyphs which, when decoded, told an elaborate tale of spaceships piloted by a race called the Dropa that crashed into the Chinese mountains. No evidence of the spaceships described by the stones (which are estimated to be 10,000 years old) has been discovered… yet.

The London Hammer

S. J. Miba/Wikimedia

If you thought the Coso Artefact was strange, wait till you hear about the London Hammer. Discovered in 1936, this ancient hammer was incased in rock that archeologists dated back to the Ordovician, over 400 million years ago. Things only got weirder from there. When the hammer itself was dated, it was discovered to be over 500 million years old, with part of the wooden handle turning into coal. The head of the hammer – which resembles other artefacts from the 19th century – was also found to have an iron purity of 96%, which wouldn’t be achievable without modern technology.

The Saqqara Bird

The Saqqara Bird, an Egyptian artefact believed to be 2,200 years old, suggests that the Wright brothers might not have been the pioneers of flight after all. The artefact strongly resembles a modern glider, complete with a vertical tail fin, and researchers believe it might be a prototype. If it is, it would suggest that the Ancient Egyptians understood the principles of aviation, and might have used the Pyramids to launch their primitive aircraft.

Antikythera Mechanism

Tilemahos Efthimiadis/Wikimedia

The Greeks paved the way for modernity in many fields, with future mathematicians, scientists and philosophers building on the foundations they laid. However, one invention in particular seems lightyears ahead of the Greeks’ other breakthroughs. Regarded as the first analogue computer, the Antikythera Mechanism was able to calculate astronomical positions and eclipses decades before they happened. The device is believed to have been created in 204BC, and it still baffles scientists.

The Baghdad Battery

Boynton/Flickr

Volta, the first officially recognised battery, was invented in 1800, so scientists were left scratching their heads when they discovered a set of three artefacts near Baghdad that appeared to be a 2,000 year old battery. Collectively known as the Baghdad Battery, the artefacts consist of a ceramic pot, an iron rod and a tube of copper, suggesting they could have been used to conduct electricity. If the device was indeed a battery, it suggests that the Parthian Empire was using technology far more advanced than was previously thought.

Piri Reis Map

Discovered in 1929, the Piri Reis Map has profound implications for both history and science. The map – which has been verified as authentic – was drawn by the Turkish admiral Peri Reis in 1513. It includes an accurate depiction of Antarctica, calling into question the belief that this region was discovered in 1820. Most astonishingly, the topography of the map suggests that Antarctica was free of ice at the time the map was drawn, which would completely upend everything that we previously believed about how the Earth’s climate has changed.